Green tea, native to China and India, has gained immense popularity for its health benefits. Now, there are more reasons to drink green tea, as scientists found consuming tea at least three times a week could help reduce the risk of premature death, living a longer and healthier life.
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In a new study published in the European Journal of Preventive Cardiology, a team of researchers has found that in roughly 100,000 participants in China, those who drank tea at least three times a week, were less likely to suffer a heart attack or stroke over the next seven years.
The project, known as the China-PAR Project, involved participants who were grouped into two groups – the habitual tea drinkers who consume three or more times a week, and the never or non-habitual tea drinkers who consume less than three times weekly. The researchers gathered baseline data and followed up on the participants after seven years.
The researchers gathered data from standardized questionnaires from the China-PAR Project, which included information on tea consumption. They then interviewed the patients or their proxies, checked hospital records, and death certificates.
Habitual tea consumption is associated with lower risks of cardiovascular disease and all-cause death. The favorable health effects are the most robust for green tea and long-term habitual tea drinkers,”
Dr. Xinyan Wang, Chinese Academy of Medical Sciences in Beijing, China
The findings of the study showed that habitual or regular tea drinkers had a 20-percent reduced risk of suffering from a stroke or a heart attack, and a 22-percent reduced risk of dying from stroke and heart disease. Particularly, the researchers found that those who regularly drink tea could expect to live 1.26 years longer at age 50, compared to those who did not regularly consume tea.
“Tea consumption was associated with reduced risks of atherosclerotic cardiovascular disease and all-cause mortality, especially among those consistent habitual tea drinkers,” the researchers wrote on the paper.
To analyze the potential influence of changes in tea drinking behavior, the team studied more than 14,000 participants. They conducted two surveys with an average of 8.2 years duration between the two. The median follow-up after the second survey was roughly five years.
In the subset, they found that tea drinkers who continued drinking in the two surveys had a 39 percent reduced risk of incident stroke and heart disease, a 56 percent lower risk of fatal stroke and heart disease, and a 29-percent decreased risk of all-cause death than those who did not consume tea drinks or the non-habitual tea drinkers.
Protective effects of tea
“The protective effects of tea were most pronounced among the consistent habitual tea drinking group. Mechanism studies have suggested that the main bioactive compounds in tea, namely polyphenols, are not stored in the body long-term. Thus, frequent tea intake over an extended period may be necessary for the cardioprotective effect,” Dr. Dongfeng Gu, Chinese Academy of Medical Sciences, said.
The researchers said that 49 percent of habitual tea drinkers consumed green tea more, while only 8 percent consumed black tea.
Green tea is rich in polyphenols, which are micronutrients people gain from plant-based foods and is a protective agent against cardiovascular disease. Green tea has also shown to protect against the common risk factors of heart disease and stroke, which include dyslipidemia, and high blood pressure.
Black tea, on the other hand, has been fully fermented, losing the polyphenols in the process. Hence, it is less likely that black tea contains antioxidants, compared to green tea.
Aside from protecting against cardiovascular disease, polyphenols in green tea improve digestion problems, diabetes, obesity, and neurodegenerative diseases.
Wang, X., Fangchao, L., Li, J., Yang, X., Chen, J., Wu, X., Lu, W., Huang, J., Li, Y., Zhao, L, Shen, C., Hu, D., Liu, X., Wu, S., and Gu, D. (2019). Tea consumption and the risk of atherosclerotic cardiovascular disease and all-cause mortality: The China-PAR project. European Journal of Preventive Cardiology. https://journals.sagepub.com/doi/10.1177/2047487319894685